From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Hawkins <dwh@ovro.caltech.edu>
Date: Wed, 12 Dec 2007 09:42:13 -0800
Subject: [U-Boot-Users] Re garding EEPROM Boot
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References: <14294144.post@talk.nabble.com>
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> We have designed MPC8548 based AMC card. We are using u-boot-1.2.0
> and it was up. Now we plan to boot the uboot in the EEPROM without using
> FLASH. Is it possible to boot the uboot in the EEPROM ?.  We are using
> AT24C64C EEPROM(64KB) and it was configured as Extended I2C addressing mode.

Its not quite clear from your comment above;
   * you've designed an 8548-based board
   * you've managed to boot it from Flash
   * now you want to boot from EEPROM

Re-read your data sheet; it is a 64k*bits* EEPROM,
or an 8KB memory. You're not going to fit much code
in that.

If the 8548 is like the 8349, the purpose of the EEPROM
is as a boot-sequencer, i.e., it can be used to program
registers in the processor memory map.

If you don't want to have Flash on the card, and the card is
a peripheral (which an AMC card is), then you can probably
have the processor boot with the core disabled, and use
something like the PCI/PCIe interface to boot the processor.
You'd have to re-read the manual; the 8349 can boot with the
e300 core disabled, have a host copy memory into DDR RAM,
and then enable the core to boot from this data.

Cheers,
Dave